Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Interest expense limitation carryforward	$ 63.0
Valuation allowance	38.0	$ 36.3
Unrecognized tax benefits that would impact effective tax rate	74.1
Unrecognized tax benefits, income tax penalties and interest expense	0.9
Accrued interest and penalties	9.6	$ 8.7
Expected decrease of unrecognized tax benefits	5.0
Domestic Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	51.5
Valuation allowance	17.3
Domestic Tax Authority \| Research Tax Credit Carryforward
Operating Loss Carryforwards [Line Items]
Tax credit carryforward	27.9
State and Local Jurisdiction
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	45.7
Foreign Tax Authority
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	66.9
Valuation allowance	$ 20.7

Interest Expense Limitation Carryforward

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 3
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 740
-SubTopic 10
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-Paragraph 15
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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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-Name Accounting Standards Codification
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